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<TITLE>[Chapter 18] 18.29 java.awt.GridBagLayout (JDK 1.0)</TITLE>
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<h2 CLASS=sect1><A CLASS="TITLE" NAME="JNUT2-CH-18-SECT-29">18.29 java.awt.GridBagLayout (JDK 1.0)</A></h2>

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<h3 CLASS=sect2><A CLASS="TITLE" NAME="JNUT2-CH-18-SECT-29.1"></A></h3>
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<P CLASS=para>
This class implements the <tt CLASS=literal>LayoutManager</tt> interface to
lay out <tt CLASS=literal>Component</tt> objects in a <tt CLASS=literal>Container</tt>.
It is the most complicated and most powerful
<tt CLASS=literal>LayoutManager</tt> in the <tt CLASS=literal>java.awt</tt> package.  It
divides the container into a grid of rows and columns (which
need not have the same width and height) and places the
components into this grid, adjusting the size of the grid
cells as necessary to ensure that components do not overlap.
Each component controls how it is positioned within this
grid by specifying a number of variables (or "constraints")
in a <tt CLASS=literal>GridBagConstraints</tt> object.
Do not confuse this class with the much simpler
<tt CLASS=literal>GridLayout</tt> which arranges components in a grid of
equally sized cells.

<P CLASS=para>
Use <tt CLASS=literal>setConstraints()</tt> to specify a
<tt CLASS=literal>GridBagConstraints</tt> object for each of the components
in the container.  Or, in Java 1.1, specify the
<tt CLASS=literal>GridBagConstraints</tt> object when adding the component
to the container with <tt CLASS=literal>add()</tt>.
The variables in this object specify the
position of the component in the grid, the number of
horizontal and vertical grid cells that the component
occupies, and also control other important aspects of
component layout.  See <tt CLASS=literal>GridBagConstraints</tt> for more
information on these "constraint" variables.
<tt CLASS=literal>setConstraints()</tt> makes a copy of the constraints
object, so you may reuse a single object in your code.

<P CLASS=para>
Note that applications should never call the
<tt CLASS=literal>LayoutManager</tt> methods of this class directly; the
<tt CLASS=literal>Container</tt> for which the <tt CLASS=literal>GridBagLayout</tt> is
registered does this.

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<PRE>
public class <tt CLASS=literal>GridBagLayout</tt> extends Object implements LayoutManager2, Serializable {
    // <tt CLASS=literal>Public Constructor</tt>
            public <tt CLASS=literal>GridBagLayout</tt>();
    // <tt CLASS=literal>Constants</tt>
            protected static final int <tt CLASS=literal>MAXGRIDSIZE</tt>;
            protected static final int <tt CLASS=literal>MINSIZE</tt>;
            protected static final int <tt CLASS=literal>PREFERREDSIZE</tt>;
    // <tt CLASS=literal>Public Instance Variables</tt>
            public double[] <tt CLASS=literal>columnWeights</tt>;
            public int[] <tt CLASS=literal>columnWidths</tt>;
            public int[] <tt CLASS=literal>rowHeights</tt>;
            public double[] <tt CLASS=literal>rowWeights</tt>;
    // <tt CLASS=literal>Protected Instance Variables</tt>
            protected Hashtable <tt CLASS=literal>comptable</tt>;
            protected GridBagConstraints <tt CLASS=literal>defaultConstraints</tt>;
            protected GridBagLayoutInfo <tt CLASS=literal>layoutInfo</tt>;
    // <tt CLASS=literal>Public Instance Methods</tt>
            public void <tt CLASS=literal>addLayoutComponent</tt>(String <tt CLASS=literal>name</tt>, Component <tt CLASS=literal>comp</tt>);  //<tt CLASS=literal> From LayoutManager</tt>
        <b>1.1</b>  public void <tt CLASS=literal>addLayoutComponent</tt>(Component <tt CLASS=literal>comp</tt>, Object <tt CLASS=literal>constraints</tt>);  //<tt CLASS=literal> From LayoutManager2</tt>
            public GridBagConstraints <tt CLASS=literal>getConstraints</tt>(Component <tt CLASS=literal>comp</tt>);
        <b>1.1</b>  public float <tt CLASS=literal>getLayoutAlignmentX</tt>(Container <tt CLASS=literal>parent</tt>);  //<tt CLASS=literal> From LayoutManager2</tt>
        <b>1.1</b>  public float <tt CLASS=literal>getLayoutAlignmentY</tt>(Container <tt CLASS=literal>parent</tt>);  //<tt CLASS=literal> From LayoutManager2</tt>
            public int[][] <tt CLASS=literal>getLayoutDimensions</tt>();
            public Point <tt CLASS=literal>getLayoutOrigin</tt>();
            public double[][] <tt CLASS=literal>getLayoutWeights</tt>();
        <b>1.1</b>  public void <tt CLASS=literal>invalidateLayout</tt>(Container <tt CLASS=literal>target</tt>);  //<tt CLASS=literal> From LayoutManager2</tt>
            public void <tt CLASS=literal>layoutContainer</tt>(Container <tt CLASS=literal>parent</tt>);  //<tt CLASS=literal> From LayoutManager</tt>
            public Point <tt CLASS=literal>location</tt>(int <tt CLASS=literal>x</tt>, int <tt CLASS=literal>y</tt>);
        <b>1.1</b>  public Dimension <tt CLASS=literal>maximumLayoutSize</tt>(Container <tt CLASS=literal>target</tt>);  //<tt CLASS=literal> From LayoutManager2</tt>
            public Dimension <tt CLASS=literal>minimumLayoutSize</tt>(Container <tt CLASS=literal>parent</tt>);  //<tt CLASS=literal> From LayoutManager</tt>
            public Dimension <tt CLASS=literal>preferredLayoutSize</tt>(Container <tt CLASS=literal>parent</tt>);  //<tt CLASS=literal> From LayoutManager</tt>
            public void <tt CLASS=literal>removeLayoutComponent</tt>(Component <tt CLASS=literal>comp</tt>);  //<tt CLASS=literal> From LayoutManager</tt>
            public void <tt CLASS=literal>setConstraints</tt>(Component <tt CLASS=literal>comp</tt>, GridBagConstraints <tt CLASS=literal>constraints</tt>);
            public String <tt CLASS=literal>toString</tt>();  //<tt CLASS=literal> Overrides Object</tt>
    // <tt CLASS=literal>Protected Instance Methods</tt>
            protected void <tt CLASS=literal>AdjustForGravity</tt>(GridBagConstraints <tt CLASS=literal>constraints</tt>, Rectangle <tt CLASS=literal>r</tt>);
            protected void <tt CLASS=literal>ArrangeGrid</tt>(Container <tt CLASS=literal>parent</tt>);
            protected GridBagLayoutInfo <tt CLASS=literal>GetLayoutInfo</tt>(Container <tt CLASS=literal>parent</tt>, int <tt CLASS=literal>sizeflag</tt>);
            protected Dimension <tt CLASS=literal>GetMinSize</tt>(Container <tt CLASS=literal>parent</tt>, GridBagLayoutInfo <tt CLASS=literal>info</tt>);
            protected GridBagConstraints <tt CLASS=literal>lookupConstraints</tt>(Component <tt CLASS=literal>comp</tt>);
}
</PRE>
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<DIV CLASS=sect2>
<h3 CLASS=sect2><A CLASS="TITLE" NAME="JNUT2-CH-18-SECT-29.2">Hierarchy:</A></h3>

<P CLASS=para>
<tt CLASS=literal>Object->GridBagLayout(LayoutManager2(LayoutManager), Serializable)</tt>

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